EP2554044A1 - Horticultural container capable of being sealed and sealing method - Google Patents

Abstract

The container (1) has an upper opening (10) surrounded by an upper edge (11) and sealed by a cover, where the cover has a slackened, flask and/or slightly concave shape. A triangular/trapezoidal shaped circumferential protuberance (12) is made of fusible material having a melting point lower than melting point of the cover on the upper edge around the upper opening. The circumferential protuberance is located at an internal border of the upper edge delimiting the upper opening and secured to the container during molding of the container. An independent claim is also included for a method for forming and sealing a horticultural container.

Description

Background of the invention

The present invention relates to the general field of horticultural containers or pots having an upper opening surrounded by an upper rim.

More particularly, the invention is concerned with horticultural containers that may be provided with a lid on their upper opening. This type of horticultural container is used in nurseries and horticulture. These sealed containers therefore have a protective cover of the substrate, this substrate being previously placed in the container. Generally, the material of the lid is a nonwoven material which then performs a dual function of occultation of light and permeability to air and water. This protective cover interferes with the proliferation of weeds. The presence of the lid thus eliminates weeding operations, both chemical and manual. This represents a gain in time and quality of culture.

In known manner, the lid is pierced at its center, in particular in the form of a cross-shaped incision for passing the stem of the plant when the latter pushes through, said horticultural container being filled with a substrate or Earth.

In a still known manner, said horticultural container comprises a pot whose cylindrical side wall with circular section in rectangle or cylindro-conical or cylindro-pyramidal, extends in elevation above a bottom wall, the upper edge said side wall being surmounted by a flat peripheral upper flange or flange, the inner edge defines an upper opening of said pot.

In a still known manner, the lid consists of a sheet of non-woven materials or of a micro-perforated film, having a permeability capable of allowing exchanges of air and water with the outside and thus allowing a sprinkling water over the lid, while avoiding fungal propagation.

The use of a protective cover on a horticultural container is, for example, known from the patent FR 2,146,516 . In this document, it is intended to use a sheet of deformable material, generally of plastic material, connected to the outline of the cache and marrying the shape of the container, or pot. This sheet of material is generally pierced in a continuous slot for engaging the rod during the establishment of these covers. These protective covers are set up manually.

However, there is also a method of protecting an automatic horticultural container. This process is described in the document EP 0 466 621 . The automatic method described in this document makes it possible to heat-seal a lid on containers used in nurseries. With this process, it is observed that the heat-sealing is often irregular and that it is difficult to ensure its quality. This penalizes the production of capped containers.

In fact, a poor quality of heat-sealing leads to repeated stops of the machine making it possible to carry out the automatic process. In the presence of defective thermocollages during production, the containers are generally discarded and discarded and this penalizes the economic efficiency of the automatic sealing process of the containers.

Beyond these problems of production of the sealed containers, it is also observed detachment of the subsequent lidding webs. Indeed, the irregularities of heat-bonding cause detachments during the various manipulations undergone by the pot, which can be the routing of the pot towards the storage areas, the wind raising the canvas and tearing, the preparation of orders, the transport etc.

These detachments favor the development of weeds since the fabric no longer fulfills its protective function.

In practice a heat-sealing temperature of the order of 240 to 250 ° C for a second and a half is sufficient to achieve the junction between the lid and the container.

More reliable heat-sealing could be achieved by increasing the heating time during the lidding step to allow more extensive melting. However, increasing the melting times leads to slower machine speeds.

On another level, it is observed that the cultivation time can not be prolonged too long without seeing the fabric of the operculum deteriorate. Indeed, with a basis weight of less than 65 g / m ² , the covers have a shelf life of about 12 months. Beyond, they deteriorate and are left allowing the light on the substrate. This leads to the development of weeds harmful to the growth of the plant.

Insofar as a thicker canvas would allow a better durability and a better efficiency from the point of view of the development of weeds since the canvas would then more obscure the light, it is desirable to change the automatic process to solutions allowing to use a thicker canvas.

In addition, during the establishment of the lid on the container by means of a flat hot plate as described below, the constituent fabric of the lid is stretched over the upper rim of the container. Subsequently, there is a detachment of the lid at the time of the hot summers due to differences in expansion of the constituent material of the container such as polypropylene and the material constituting the lid. A thicker operculum would reduce this phenomenon.

However, currently, the use of a thicker canvas is not compatible with a regular and efficient heat sealing. A cover that is too thick gives rise to irregularities of heat-sealing which penalize the production by machine stops and / or scraps of part of the defective production. These gluing irregularities cause detachments during the various manipulations experienced by the pot such as the delivery of the pot to the storage air or during transport, the wind can lift the lid and thus tear it off.

In EP 1 681 245 discloses a polyester container having certain crystallinity characteristics, comprising a top flange to be covered by heat sealing with a cover. Due to the characteristics of the polyester resin used, the temperature and the melting time of the material of the container are relatively too high which limits the possibilities for the choice of the lid. In this document, it is proposed to insert a bead of adhesive material forming a protuberance on the underside of the lid or over the upper rim of the container.

So, in EP 1681245 it is proposed to implement a protuberance in a material having reduced crystallinity characteristics in the center and / or peripheral portion of the upper rim of the container. The method and device described in EP 1 681 245 are not suitable for making a horticultural container in another material, especially in polypropylene, the lid of which is made of a sheet of flexible or semi-rigid material of the type described above.

In the document FR 2 629 424 a thermoplastic container having a flange for receiving a lid is also described, the upper face of the flange being provided with a solid and continuous bead permitting the thermo-welding of said lid and thus constituting a gasket with an excess thickness of the flange between the container and the lid, permitting the thermo-welding of said lid. To do this, the bead forming a protrusion on the surface of the upper rim of the container after heat-sealing is shifted towards the center of the upper flange relative to the inner edge of the upper rim, because it is formed by stamping over this one.

Object and summary of the invention

The main purpose of the present invention is therefore to overcome the disadvantages encountered with horticultural containers of the prior art and with the lidding processes described in the prior art, by proposing an improved horticultural container having an upper opening surrounded by a horticultural container. upper flange and adapted to be sealed by a lid, the container comprising a circumferential protrusion fusible material of melting temperature lower than the melting temperature of the lid, on its upper flange around its upper opening.

The presence of a circumferential protuberance on the upper rim of the horticultural container, around its upper opening, makes it possible to better locate the melting zone of the pot. Indeed, according to the principle of sealing, the melting temperature of the material used for the seal is greater than the melting temperature of the material constituting the container to be capped. In this way, the material placed on the upper rim of the pot melts and impregnates in the material of the lid.

According to the present invention, the circumferential protuberance is located at the inner edge of the upper flange delimiting said upper opening.

The presence of the circumferential protuberance at the inner edge of the upper rim makes it possible to better consolidate the inner edge of the upper rim of the horticultural container. However, this inner edge is the most stressed compression support zone during heat sealing of the lid over the upper edge. The circumferential protuberance is then ideally located because it allows to make a localized weld at the point ensuring the best compressive strength during the operation of the heat sealing of the lid.

In addition, the fact that the protuberance is in extension of the side wall of the horticultural container, just above it in elevation, further facilitates the stacking and unstacking of the pots on each other before putting in place of the operculum. Indeed, the position of said protuberance makes it possible to stiffen said flange, in particular when the thickness of the constituent material of said horticultural container is relatively small, especially less than 2 mm.

And, in this case, the upper rim deforms relatively easily and tends to make the stack unstacking, after stacking, relatively difficult in practice.

On the other hand, this position of the protuberance also contributes to favoring the establishment of a lid with a slightly flaccid and / or concave shape of the lid, allowing to withstand a differential expansion of the constituent material of the horticultural container with respect to the expansion of the lid, especially in case of high temperature in summer.

This characteristic of flaccid and / or concave shape of the lid is also favored by the fact that it is possible to use a lid of relatively larger basis weight, in particular of at least 65 g / m ² .

According to the principles of sealing, the seal must be the result of a compromise between a sufficient thickness to confer a correct mechanical strength and a sufficiently small thickness to allow the conduction of heat in its thickness until fusion of the material composing the circumferential protuberance.

In the presence of the circumferential protuberance, the fusion is localized on this protuberance and is thus more concentrated with respect to a lidding carried out directly on the upper rim of the container. With the invention, thicker webs above 65 g / m ² can then be welded in a correct manner due to the presence of the circumferential protuberance. It is therefore possible to use thicker and therefore more opaque nonwovens, these nonwovens then solving the problem of the service life. Indeed, the use of a fabric thicker than 65 g / m ² allowed by the invention, allows to obtain more opacity, and therefore a better occultation of the light, and a greater thickness which confers a better resistance to perforation and better durability of the lid.

One of the weaknesses of the method known in the prior art is the absence of heat sealing on the largest flat surface, that is, on the horizontal portion of the upper rim of the pot represented by the horizontal portion of the flange. Indeed, heat sealing is generally at the angle formed at the junction of the flange and the wall of the pot. Thus, at the time of the pressure, there is a crushing and gluing on the inside angle of the flange, resulting in welding on the internal contour of the flange, irregular and often faulty. The invention solves this problem.

Thus, the invention makes it possible to optimize the contact between the fabric of the lid and the container under the effect of a sealing plate. It has indeed been noticed that the reduction of the point of contact between the membrane of the lid and the container makes it possible to obtain a heat-sealing operation of better quality.

More particularly, the circumferential protrusion is integrated into the container during the molding of the container itself. In other words, said side wall and upper flange and said protuberance of said container are made of the same plastic material and come from material.

In a preferred application of the invention, the horticultural container according to the invention is coated with a lid consisting of a sheet of nonwoven material maintained glued by local impregnation of the material of said circumferential protuberance obtained by melting said material of said circumferential protuberance, preferably said horticultural container filled with soil or a substrate.

More preferably, said lid having a relaxed shape, flaccid and / or slightly concave, preferably comprising a central bore, in particular cross-shaped, able to let the stem of a plant when it grows through.

• ledit opercule est réalisé dans une feuille de matériau fibreux non-tissé, de préférence à base de fibres de polyester et viscose ; et
• ledit opercule présente un grammage d'au moins 65g/m², de préférence inférieur à 100g/m², de préférence encore de 65 à 75g/m².

Due to the consolidation and stiffening of said flange, it is possible to implement a said cap, having the following particular advantageous characteristics:

• said lid is made of a sheet of fibrous nonwoven material, preferably based on polyester and viscose fibers; and
• said cover has a basis weight of at least 65g / m ^2, preferably less than 100g / m ^2, more preferably from 65 to 75g / m ^2.

This upper limit value of 100 g / m ² is dictated essentially by the necessity that the thickness of the lid must be sufficiently reduced to allow rapid conduction of heat through its thickness in order to obtain a rapid melting of the constituent material. said protrusion on the underside of the lid.

• ladite protubérance présente une hauteur inférieure ou égale à l'épaisseur dudit rebord supérieur et de ladite paroi latérale dudit contenant horticole, et, de préférence, ladite protubérance présente une hauteur supérieure à 50% de l'épaisseur dudit rebord latéral et de ladite paroi latérale dudit contenant horticole ; et
• l'épaisseur de ladite protubérance dudit contenant horticole est de 0,5 à 2 mm, de préférence de 0,8 à 1 mm ;
• l'épaisseur dudit rebord supérieur et de ladite paroi latérale dudit contenant horticole est de 0,5 à 2 mm, de préférence de 0,8 à 1 mm.

According to other advantageous characteristics:

• said protuberance has a height less than or equal to the thickness of said upper rim and said side wall of said horticultural container, and, preferably, said protuberance has a height greater than 50% of the thickness of said lateral rim and said side wall; said horticultural container; and
• the thickness of said protuberance of said horticultural container is 0.5 to 2 mm, preferably 0.8 to 1 mm;
• the thickness of said upper flange and said side wall of said horticultural container is 0.5 to 2 mm, preferably 0.8 to 1 mm.

Thus, the protuberance after heat sealing of the lid is fully melted and no longer forms an extra thickness between the upper flange and the lid.

In a preferred embodiment, the section of the circumferential protuberance in a vertical axial plane of said horticultural container is triangular or trapezoidal.

With such a section of the circumferential protuberance, it ensures an optimal melting thereof starting with the tip of the triangle or trapezium and moving towards its base gradually increasing the amount of molten material. Optimum impregnation of the material constituting the horticultural container in the web of the lid is then obtained. Also, the pointed shape of the circumferential protuberance allows a faster melting start of the fuse material in contact with the fabric, that is to say the circumferential protuberance, since the contact zone is then circular of small width.

Preferably, the section of the protuberance in a said vertical axial plane is trapezoidal with a small upper base of said trapezoid width less than or equal to one third of the width of the large lower base of said trapezium.

This embodiment makes it possible to obtain an annular contact between the lid and the container from the beginning. The overall diamond shape of the trapezoidal circumferential protuberance allows to maintain a rapid melting thereof and an optimal impregnation in the membrane of the lid while stabilizing the contact between the lid and the container at the beginning of the lidding step.

In a preferred embodiment, the circumferential protrusion is integrated with the container during the molding of the container itself.

The direct integration of the circumferential protuberance on the container during the molding of the horticultural container makes it possible to manufacture the horticultural container according to the invention with a single manufacturing step which is a molding step.

In a preferred embodiment, the integration of the circumferential protuberance during molding is obtained by pre-grooving the mold of the container.

The simple realization of a preliminary grooving on the mold to obtain the container by molding makes it possible to implement the invention at a lower cost. Indeed, an already known mold can be used to implement the invention as soon as it is likely to be grooved at the upper rim of the container.

Obtaining such a container is permitted by the invention, typically after applying an automatic method applying heat to the circumferential protuberance to cause its fusion according to the principles of sealing a container.

Such a mold makes it possible to obtain the preferential embodiment of a horticultural container according to the invention.

• réaliser un contenant horticole présentant une ouverture supérieure entourée d'un rebord supérieur d'une protubérance circonférentielle en matière fusible sur son rebord supérieur autour de son ouverture supérieure,
• poser un opercule tramé présentant une température de fusion supérieure à la température de fusion de la protubérance circonférentielle sur le rebord supérieur, cet opercule reposant alors sur la protubérance circonférentielle,
• amener une plaque chauffante de taille telle qu'elle recouvre la protubérance circonférentielle sur la protubérance circonférentielle,
• provoquer la fusion de la protubérance circonférentielle permettant de sceller l'opercule par pénétration de matière fondue dans la trame de l'opercule.

The invention also relates to a process for lidding a horticultural container comprising the successive steps of:

• producing a horticultural container having an upper opening surrounded by an upper flange of a circumferential protrusion of fuse material on its upper flange around its upper opening,
• placing an operculum having a melting temperature greater than the melting temperature of the circumferential protuberance on the upper flange, this operculum then resting on the circumferential protuberance,
• bringing a hot plate of such size that it covers the circumferential protuberance on the circumferential protuberance,
• causing the circumferential protuberance to merge, sealing the lid by penetration of molten material into the frame of the lid.

This method makes it possible to obtain a sealed container with good wear resistance and with a seal quality assurance of the lid.

Advantageously, the first step is performed by molding, with a mold of the container comprising a groove at the molding area of the upper flange, said groove being able to form a said circumferential protuberance located just inside the upper flange during molding said container.

Such a mold therefore allows the molding of a horticultural container according to the invention directly and in a single molding step.

According to a preferred feature, the step of supplying the heating plate consists in bringing a heating plate having an embossing protrusion preferably frustoconical in shape, of smaller diameter than the upper opening of the horticultural container.

This embossing on the underside of the heating plate and in contact with the central portion of the lid provides a relative thermal insulation of said central portion of the lid, which preserves the structure of the material constituting the lid and therefore its resistance in time, only the circumferential peripheral portion of the plate vis-à-vis said protuberance being subjected to the higher temperature of the heating plate effecting the melting of said protuberance.

This particular characteristic of the plate also makes it possible to obtain lidding with a relaxed web of flaccid and / or concave shape. By relaxing the canvas, it avoids the takeoff of it. This improves the effectiveness of the weed control function.

This characteristic also makes it possible to avoid excessive tension of the fabric due to the differences in expansion between the different materials. Indeed, it is known that delamination of the fabric occurs at the time of high summer heat due to differences in expansion between the constituent material of the horticultural container and the nonwoven. This is due to a phenomenon of excessive tension of the fabric on the container during the establishment of the latter, by means of a heat sealing device, typically a flat hotplate.

Brief description of the drawings

• Les figures 1A et 1B montrent un contenant horticole selon l'invention et un détail du rebord supérieur du contenant selon l'invention ;
• La figure 2 montre une section particulière d'une protubérance circonférentielle selon l'invention ;
• Les figures 3A et 3B montrent schématiquement le procédé d'operculage selon l'invention ;
• La figure 4 montre une plaque chauffante selon un mode de réalisation particulier du procédé d'operculage selon l'invention ;
• Les figures 5A, 5B et 5C montrent schématiquement le procédé d'operculage selon l'invention avec la plaque chauffante de la figure 4 et le pot avec operculage obtenu ainsi.

Other features and advantages of the present invention will emerge from the description given below, with reference to the accompanying drawings which illustrate an embodiment having no limiting character. In the figures:

• The Figures 1A and 1B show a horticultural container according to the invention and a detail of the upper rim of the container according to the invention;
• The figure 2 shows a particular section of a circumferential protuberance according to the invention;
• The Figures 3A and 3B schematically show the sealing process according to the invention;
• The figure 4 shows a heating plate according to a particular embodiment of the lidding process according to the invention;
• The FIGS. 5A, 5B and 5C schematically show the lidding process according to the invention with the heating plate of the figure 4 and the pot with lidding obtained as well.

Detailed description of an embodiment

• The Figure 1A shows a horticultural container 1 comprising a bottom wall 1b surmounted by a cylindrical-conical side wall 1a with an upper opening 10, surrounded by a collar or upper flange 11, here materialized by a slight shoulder on the contour of the opening 10. Such a horticultural container or pot structure is well known to those skilled in the art.
• The Figure 1B shows a detail of the upper rim 11 of the horticultural container 1 according to the invention. The upper flange 11 is here provided on its inner edge with a circumferential protrusion 12. Here, the circumferential protuberance 12 has a triangular section rising above the upper flange 11. Here, in a preferred embodiment, the wall of the pot 1 is located in line with the protuberance 12.

Typically, the height of the circumferential protuberance will be of the order of the thickness of the upper flange 11 and the side wall 1a of the pot 1, here of the order of 1 mm. This height will be advantageously variable depending on the thickness of the wall of the pot. The thicker the walls of the pot, the greater the height of the protrusion. Typically, circumferential protrusion heights of between 0.5 mm and 7 mm will be observed.

The figure 1C shows a perspective view of the pot according to the invention shown on the Figures 1A and 1B .

The horticultural container 1 is advantageously made of a material of polypropylene type, for example of black color. The container 1 will advantageously have a smooth appearance and produced according to a method by molding, the mold having been previously manufactured by the manufacturer. The material from which the container is made typically melts between 160 and 180 ° C.

The figure 2 shows another section for a circumferential protuberance 12 according to the invention. Here, the section is trapezoidal. Advantageously this section has a large base width 0.75 mm, a height of 0.80 mm and a small base with a width of 0.25 mm. This section is equivalent to a truncated triangular section on its upper part. This characteristic makes it possible to obtain a wider annular melting zone than when a triangular section is used.

The method according to the invention is illustrated with the aid of the following figures. The figure 3A shows the pot 1, a lidding web 2 and a hot plate 3, before the realization of the lidding.

The fabric advantageously has a fibrous nonwoven structure allowing gaseous exchange and a certain permeability allowing sprinkling spray which is well suited to this type of container. Lidding with such a nonwoven fabric also avoids fungal propagation.

Typically, the fabric is made of non-woven material based on polyester and viscose fibers having a melting point higher than the polypropylene constituting the horticultural container 1, marketed by TEFISA (Spain). The fabric is partially biodegradable, as the viscose deteriorates over time, which is not the case of the polyester and the binder for making the fabric. However, it has been observed that webs that are fine or less than 65 g / m ² exhibit rapid degradation over a period of 12 months.

Typically, the color of the fabric is black and, in all cases, opaque to prevent seed germination. The melting temperature of the fabric is generally of the order of 350 ° C.

The heating plate 3 has a heating mechanism that allows it to reach the temperature of 275 ° C at the time of welding. The plate is advantageously made from aluminum coated with a PTFE (Teflon) coating.

The figure 3B shows the phenomenon occurring when the heating plate 3 presses on the upper edge 11 of the horticultural container 1. Typically, the compression of the heating plate 3 is 5 kg per square of 20 mm side. It is observed that the pressure on the upper rim 11 of the pot 1 causes a slight folding it downward. It is well understood in this figure, the advantageous positioning of the circumferential protuberance 12 at the inner edge of the upper rim 11. In fact, its presence adds material at this very particular point of the upper rim 11 which runs just above the side wall of the horticultural container 1.

The fact that the circumferential protuberance 12 is in extension of the side wall, in elevation on the pot 1, also makes it possible not to hinder the stacking and de-stacking of the pots on each other. Note that the circumferential protuberance 12 advantageously has a height substantially equal to the thickness of the pot, between 0.8 and 1 mm.

It is also known that a space must be maintained between the upper surface of the substrate introduced into the horticultural container 1 and the lid 2, so as to prevent germination of the weed seeds inside the operculum 2 under the effect of the moisture of the substrate, and this, in case of contact between the substrate and the lid 2. There is generally sufficient space between the high point of the substrate and the plane of the upper rim 11 of the horticultural container 1 .

So, as shown on the figure 4 the invention is concerned with further improving the sealing of the horticultural container 1 by ensuring that the lid 2 has a slightly concave shape as soon as it is sealed. This characteristic is enabled by the presence of a space between the substrate and the plane of the upper rim 11.

By ensuring a concavity of the lid, it is slightly relaxed. This allows it to withstand the differential expansion of the horticultural container 1 with respect to its own dilation. This is particularly useful in case of high temperatures in the summer and, in particular, for temperatures above or equal to 40 ° C. These temperatures are, indeed, well known to cause excessive tension of the lid 2.

The invention thus also relates to a lidding process, wherein the heating plate, denoted 3 'on the figure 4 has been modified to include a central embossment protrusion 31 on the underside intended to come into contact with the central portion of the lid, having an at least partially conical surface. Advantageously, as represented on the figure 4 , the protrusion 31 is truncated conical, the base of the cone having a diameter, preferably equal to 90 mm, while the surface at the truncation of the cone has a diameter of 30 mm. It will be noted here that the base of the cone will have a dimension smaller than the minimum diameter of the smallest upper opening 10 which can be sealed with this heating plate 3 '. The plate 3 'may, for its part, advantageously have a fairly large diameter, for example 240 mm. The protrusion 31 advantageously has a thickness of 20 mm and is centered on the plate 3 ', for example, leaving 75 mm on either side. The thickness of the plate 3 'may for example be of the order of 35 mm, as is already the case with known flat hot plates.

The Figure 5A shows the heating plate 3 'of the figure 4 in preparation and heating above the pot 1 and the operculum 2. On the Figure 5B , the heating plate 3 'is in contact with the cap 2 and causes a relaxation thereof with respect to the method shown in FIG. figure 3 thanks to the presence of the central protrusion 31 on the heating plate 3 '. The result obtained is shown on the Figure 5C where the lid 2 is relaxed, or slightly flaccid. This avoids excessive tension on the contour of the lid fixed by the method of the invention on the contour of the pot during hot weather.

Finally, it should be noted that various implementations can be made according to the principles of the invention.

In addition, the presence of this embossing on the underside of the heating plate provides an additional advantageous technical effect in that being thicker, it rises in temperature less rapidly than the peripheral portion and thus protects the fabric of the cover in its central part of any deformation in its structure that could result from an excessive rise in temperature.

In this case, the heating plate has the highest temperature in its peripheral zone vis-à-vis said protuberance.

Thus, when the operculum is pierced at its center as is the case to allow the passage of the plant stem in growth, the parts of the fabric cut at its center remain flat and do not deform curvature, as this would be the case if the structure of the material constituting the fabric underwent excessive heat in its central part.

Claims (13)

Horticultural container (1) having an upper opening (10) surrounded by an upper flange (11) and adapted to be sealed by a lid (2), said container (1) comprising a circumferential protuberance (12) of temperature fusible material of melting less than the melting temperature of the lid (2) on its upper rim (11) around its upper opening (10), characterized in that the circumferential protuberance (12) is located at the inner edge of the upper flange (11) delimiting said upper opening (10). Horticultural container according to claim 1, characterized in that the circumferential protrusion (12) is integrated in the container during the molding of the container (1) itself. Container according to one of the preceding claims, characterized in that it is covered with a cover consisting of a web or sheet of nonwoven material kept glued by local impregnation of the material of said circumferential protuberance (12) obtained by melting said material of said circumferential protuberance (12) of melting temperature fusible material lower than the melting temperature of the seal (2), preferably said horticultural container being filled with earth or a substrate. Horticultural container according to one of Claims 1 to 3, characterized in that it is coated with a lid having a relaxed, flaccid and / or slightly concave shape, preferably comprising a central bore capable of allowing the stem to pass through. a plant when it grows through said piercing. Horticultural container according to one of the preceding claims, characterized in that said lid is made of a sheet of fibrous nonwoven material, preferably based on polyester and viscose fibers. Horticultural container according to one of the preceding claims, characterized in that said cover has a basis weight of at least 65g / m ^2, preferably less than 100g / m ^2, more preferably from 65 to 75g / m ^2. Horticultural container according to the preceding claims, characterized in that the section of the circumferential protuberance (12) is triangular or trapezoidal. Horticultural container according to one of the preceding claims, characterized in that said protuberance (12) has a height less than or equal to the thickness of said upper rim (11) and the side wall (1a) of said horticultural container, and preferably, said protuberance has a height greater than 50% of the thickness of said upper rim and said side wall of said horticultural container. Horticultural container according to one of the preceding claims, characterized in that the thickness of said protrusion is 0.5 to 2 mm, preferably 0.8 to 1 mm. Horticultural container according to one of claims 8 or 9, characterized in that the thickness of said upper rim and said side wall of said horticultural container are 0.5 to 2 mm, preferably 0.8 to 1 mm. A process for producing and sealing a horticultural container (1) according to claims 1 to 10, comprising the successive steps of: - producing a horticultural container (1) having an upper opening (10) surrounded by an upper flange (11) of a circumferential protrusion (12) of fusible material on its upper rim (11) around its upper opening (10) , - Laying an operculum (2) having a melting temperature higher than the melting temperature of the circumferential protuberance (12) on the upper flange (11), the seal (2) then resting on the circumferential protuberance (12), bringing a heating plate (3) of such size that it covers the circumferential protuberance (12) in contact with the circumferential protuberance, - Thus cause the melting of the circumferential protuberance (12) for sealing the lid (2) by penetration of the melt of the circumferential protuberance (12) in the frame of the lid (2). Process according to Claim 11, characterized in that the first step of producing said container is carried out by molding with a mold of the container (1), comprising a groove at the molding area of the upper flange (11), said groove being able to form a said circumferential protuberance located just inside the upper flange (11) during the molding of said container. Method according to one of claims 11 or 12, characterized in that the step of supplying the heating plate (3) comprises bringing a heating plate (3 ') having a central embossing protrusion on the underside ( 31), preferably frustoconical in shape, of smaller diameter than the upper opening (10) of the horticultural container (1).

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